Brushless DC-Servomotors Series 0308 ... B

2 Pole Technology, sensorless

Key Features

Nominal voltage:

3 V

Rated torque up to:

0.013 mNm

No-load speed up to:

61000 min⁻¹

Stall torque up to:

0.026 mNm

Diameter:

3 mm

Length:

8.4 mm

Advantages

Extremely compact design. Diameters ranging from 3 mm to 5 mm

For applications where space is very limited

2-pole design with medium to high speeds

Matching, highly compact gearheads available

Matching speed controllers available

Variants:

Values at 22° and nominal voltage		Value
Nominal voltage	U_N	3 V
Terminal resistance, phase-phase	R	34 Ω
Efficiency, max.	η_max.	20 %
No-load speed	n₀	61000 min⁻¹
No-load current	I₀	0.027 A
Stall torque	M_H	0.026 mNm
Friction torque, static	C₀	0.00177 mNm
Friction torque, dynamic	C_V	1.09 ·10⁻⁷ mNm/min⁻¹
Speed constant	k_n	29800 min⁻¹/V
Back-EMF constant	k_E	0.033 mV/min⁻¹
Torque constant	k_M	0.32 mNm/A
Current constant	k_I	3.12 A/mNm
Slope of n-M curve	Δn/ΔM	3200000 min⁻¹/mNm
Terminal inductance, phase-phase	L	60 µH
Mechanical time constant	τ_m	7 ms
Rotor inertia	J	0.0002 gcm²
Angular acceleration	α_max.	1323 ·10³rad/s²
Thermal resistance	R_th1/R_th2	60 / 300 K/W
Thermal time constant	τ_w1/τ_w2	0.5 / 45 s
Operating temperature range		-30 ... 60 °C
Winding temperature, max.		60 °C
Housing material		Nickel alloy
Mass		0.35 g
Direction of rotation		electronically reversible
Speed up to	n_max.	96000 min⁻¹
Number of pole pairs		1
Hall sensors		without
Magnet material		NdFeB

Values at 22° and nominal voltage		Value
Nominal voltage	U_N	3 V
Terminal resistance, phase-phase	R	34 Ω
Efficiency, max.	η_max.	20 %
No-load speed	n₀	61000 min⁻¹
No-load current	I₀	0.027 A
Stall torque	M_H	0.026 mNm
Friction torque, static	C₀	0.00177 mNm
Friction torque, dynamic	C_V	1.09 ·10⁻⁷ mNm/min⁻¹
Speed constant	k_n	29800 min⁻¹/V
Back-EMF constant	k_E	0.033 mV/min⁻¹
Torque constant	k_M	0.32 mNm/A
Current constant	k_I	3.12 A/mNm
Slope of n-M curve	Δn/ΔM	3200000 min⁻¹/mNm
Terminal inductance, phase-phase	L	60 µH
Mechanical time constant	τ_m	7 ms
Rotor inertia	J	0.0002 gcm²
Angular acceleration	α_max.	1323 ·10³rad/s²
Thermal resistance	R_th1/R_th2	60 / 300 K/W
Thermal time constant	τ_w1/τ_w2	0.5 / 45 s
Operating temperature range		-30 ... 60 °C
Winding temperature, max.		60 °C
Housing material		Nickel alloy
Mass		0.35 g
Direction of rotation		electronically reversible
Speed up to	n_max.	96000 min⁻¹
Number of pole pairs		1
Hall sensors		without
Magnet material		NdFeB

Operating Area

Recommended operation areas at nominal voltage 3 V

The diagram indicates the recommended speed in relation to the available torque at the output shaft for a given ambient temperature of 22°C.

The diagram shows the motor in a completely insulated as well as thermally coupled condition (R_th2 50% reduced).

The nominal voltage (U_N) curve shows the operating point at nominal voltage in the insulated and thermally coupled condition. Any points of operation above the curve at nominal voltage will require a higher operating voltage. Any points below the nominal voltage curve will require less voltage.

Characteristic curves of motor